Unit 5 : Cell Growth and Reproduction
Lesson 1: Genes and Proteins Synthesis
OBJECTIVES:
• Genes and Protein Synthesis
• The Cell Cycle, DNA Replication, and Mitosis
• Genes, Alleles, and Meiosis
DNA
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________________________________________________________
Blueprint for building proteins.
Monomers: nucleotides (_____________, base, phosphate group)
BASES
• Bases of DNA are:
• __________________ (A)
• __________________ (C)
• __________________ (G)
• __________________ (T)
DNA is a double stranded molecule.
Adenine bonds with _____________________
Cytosine bonds with _____________________
CODONS
• Group of three nucleotides is called a _____________________.
• The sequence of nucleotides determines what _________________________ will be added to make a
protein.
• A region of DNA that codes for a protein is a __________________.
• *Remember the monomer of protein is an ____________________________.
• Gene expression: The process by which genetic information is used to make a protein.
CHROMOSOMES
• DNA winds around proteins called ____________________, which coil and condense to make
chromosomes.
• Prokaryotes have DNA that winds into a circle.
**QUESTION: One strand of DNA contains the base sequence ACGGTATCG.
What base sequence does the complementary strand contain?
a. CTAAGCGTA
b. ACGGTATCG
c. TGCCATAGC
d. GCTATGGCA
TRANSCRIPTION
• DNA is ______________ and a “transcript” of the information _______________________________ into the
cytoplasm in order to be read to make a protein.
• The “transcript” (or copy of DNA) is called ________________.
• RNA is only single stranded and has _______________ instead of Thymine.
TRANSCRIPTION CONT..
• RNA (ribonucleic acid)
• Transcription : process when _________________________ into a strand of mRNA. (____________________
RNA)
• Steps to Transcription:
• 1. _________________________________ the two strands of DNA.
• 2. One strand of DNA is transcribed into _________________.
• 3. RNA _________________________ (protein) attaches the correct RNA nucleotide to build the strand
of mRNA.
TRANSLATION
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There are ___________ different amino acids that make up proteins.
The order of amino acids in a protein determines the protein’s 3-d _______________________________.
Translation: process of ____________________________ from mRNA.
Proteins are made in the ____________________________________.
TRANSLATION CONT..
• Ribosomes contain rRNA (___________________ RNA) and protein.
• Steps to Translation:
• 1. mRNA attaches to a ribosome.
• 2. The ribosome reads the mRNA and tRNA (________________ RNA) will transfer the correct
amino acid onto the chain to build a protein.
• 3. The ______________________ is the region on tRNA that is complementary to the codon found on
the mRNA.
• Ex. UGG is the codon for the amino acid tryptophan. A tRNA molecule that binds to
tryptophan has the complementary anticodon sequence ACC.
TRANSLATION CONT..
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There are “____________” codons and “stop” codons that helps the tRNA determine where to start
building a __________________ and where to stop.
****QUESTION
Amino Acid
Anticodon
Serine
AGA
Valine
CAA
Leucine
GAU
What mRNA sequence was used to make a polypetide strand of serine, valine, and leucine?
Protein Synthesis in the Cell
• Proteins are made on ______________________________.
• Ribosomes are either ___________________________ or are free floating in the cytoplasm.
• If the protein is being made for the plasma membrane they will be made on the rER.
• If protein is being made for the cell to use they will be made on free ribosomes.
• The protein made on rER will be packed into ____________________.
• These vesicles will travel to the ____________________________, then will be modified and sent to the
cell membrane.
***QUESTION
• Which organelle is not involved in the synthesis and secretion of a protein from the cell?
• A. Ribosome
• B. Smooth ER
• C. Golgi apparatus
• D. Plasma membrane
ASSIGNMENT – KEYSTONE PACKET
• Complete ques. 1-6
• Pg. 112 & 113